Copyright © 2016 by Elsevier, Inc. All rights reserved. Geropharmacology

Pharmacokinetics  Study of the movement and actions of a drug in the body  Absorption  Distribution  Metabolism  Excretion Copyright © 2016 by Elsevier, Inc. All rights reserved. 2

Pharmacokinetics (Cont.)  Absorption  Route of administration  Bioavailability  Amount of drug that passes through absorbing surfaces in body Copyright © 2016 by Elsevier, Inc. All rights reserved. 3

Pharmacokinetics (Cont.)  Distribution  Once absorbed, systemic circulation transports drug to receptor site on target organ  Distribution to organs with lower blood flow occurs more slowly and results in lower concentrations  Depends on the availability of plasma protein in the form of lipoprotein, globulins, and especially albumin Copyright © 2016 by Elsevier, Inc. All rights reserved. 4

Pharmacokinetics (Cont.)  Excretion  Drugs and their metabolites are excreted in sweat, saliva, and other secretions but primarily through kidneys  Renal drug excretion occurs when drug is passed through kidney and involves glomerular filtration, active tubular secretion, and passive tubular reabsorption  Assessment of creatinine clearance rates an important consideration in older adults to prevent drug toxicity Copyright © 2016 by Elsevier, Inc. All rights reserved. 5

Pharmacodynamics  Physiological interaction between medication and the body  The older a person gets, the more likely he or she will have altered unreliable pharmacodynamics Copyright © 2016 by Elsevier, Inc. All rights reserved. 6

Issues in Medication Use  Polypharmacy  Taking multiple medications at same time, approximately five or more  Above five medications increase risk for frailty, disability, death, and falls  Increased risk for medication interactions  Increased risk for adverse events Copyright © 2016 by Elsevier, Inc. All rights reserved. 7

Issues in Medication Use (Cont.)  Medication Interactions  The more prescribed medications or other substances, the greater the possibility of interactions  When given at the same time may potentiate each other  Types of interactions to consider:  Medication-herb/supplement interactions (Table 9-1)  Medication-food interactions (Table 9-2)  Medication-medication interactions Copyright © 2016 by Elsevier, Inc. All rights reserved. 8

Safe Administration of Medications via Enteral Feeding Tubes  High risk for medication errors  Possible outcomes:  Occluded tube  Reduced drug effect  Drug toxicity  Patient harm  Patient death Copyright © 2016 by Elsevier, Inc. All rights reserved. 9

Safe Administration of Medications via Enteral Feeding Tubes (Cont.)  The three most common errors  Incompatible route  Improper preparation  Improper administration  Can lead to altered absorption, distribution, excretion, or contribute to alterations in pharmacodynamics Copyright © 2016 by Elsevier, Inc. All rights reserved. 10

Issues in Medication Use  Adverse Drug Reactions (ADR) or Events  Occurs when there is a noxious response to a medication  Corticosteroids, anticoagulants, sedative hypnotics, immunosuppressants, and chemotherapeutic agents are of concern  Allergic reactions are more common in the older adult as the immune system decreases in function  To minimize the likelihood of ADRs: “start low, go slow, but go” Copyright © 2016 by Elsevier, Inc. All rights reserved. 11

Issues in Medication Use (Cont.)  “Beer’s Criteria”  Potentially inappropriate medication  Drugs identified to have a higher than usual risk when used in older adults (Box 9-7)  Overwhelming benefit versus risk documentation when prescribing these drugs considered a standard of practice Copyright © 2016 by Elsevier, Inc. All rights reserved. 12

Issues in Medication Use (Cont.)  Psychoactive Medications  Affect mental function, which in turn can affect behavior  Medications with psychoactive properties have a higher risk for adverse events  Never be used as a “quick fix”  Requires a thorough assessment  Antipsychotics, when used appropriately and cautiously, can provide relief from frightening and distressing symptoms Copyright © 2016 by Elsevier, Inc. All rights reserved. 13

Issues in Medication Use (Cont.)  Issues Associated with Psychoactive Medications  Malignant syndrome  Movement disorders  Acute dystonia  Akathisia  Parkinsonian symptoms  Tardive dyskinesia Copyright © 2016 by Elsevier, Inc. All rights reserved. 14

Promoting Healthy Aging: Implications for Gerontological Practice  Ensure medication is used appropriately, effectively, and safely  Monitor for signs and symptoms of ADRs  Prompt recognition of changes in patient status that can affect drug regimen  Patient and family education on purpose and side effects of all medications to enhance safe compliance with drug therapy Copyright © 2016 by Elsevier, Inc. All rights reserved. 15

Promoting Healthy Aging: Implications for Gerontological Practice (Cont.)  Assessment  The “brown bag approach” asks the person to bring in all medications being taken, including over the counters, herbals, and neutraceuticals or dietary supplements  Ask person how he or she actually takes medicine rather than depending on label  Analysis assessment findings related to medications (Box 9-8) Copyright © 2016 by Elsevier, Inc. All rights reserved. 16

Promoting Healthy Aging: Implications for Gerontological Practice (Cont.)  Education  Most common intervention to promote medication adherence  Promotion of healthy aging related to medication use  Key persons  Environment  Timing  Communication  Reinforce teaching Copyright © 2016 by Elsevier, Inc. All rights reserved. 17

Promoting Healthy Aging with Safe Medication Use  Education  Assessment of patient’s readiness to learn, ability to comprehend, and functional capacity to incorporate lifestyle adaptations for medication management Pamphlets and booklets written in lay terms and in appropriate language and reading level should be available Copyright © 2016 by Elsevier, Inc. All rights reserved. 18

Promoting Healthy Aging with Safe Medication Use (Cont.) Reducing Adverse Medication Events Copyright © 2016 by Elsevier, Inc. All rights reserved. 19

Question 1 Drugs and their metabolites are excreted primarily through: a. sweat. b. saliva. c. liver. d. kidneys. Copyright © 2016 by Elsevier, Inc. All rights reserved. 20

Question 2 Which of the following is most likely to mimic symptoms of Parkinson’s disease? a. Antidepressants b. Antipsychotics c. Antianxiety agents d. Mood stabilizers Copyright © 2016 by Elsevier, Inc. All rights reserved. 21